RETURN
SPRING
PRIMARY SHOE
WHEEL CYL.
BOLT
RETURN
SPRING
LINK ADJUSTER (UPPER)
SPRING, AUTOMATIC
ADJUSTER
SECONDARY
SHOE
NUT, PIVOT R.H.
ADJUSTER
ASf02032
NUT, PIVOT L.H.
LEVER
Figure 2-32.--Brake assembly, self-adjusting.
inspections. The interval of these inspections is usually
wheel is locked by the brake shoes, and then back off
specified in the applicable instruction manual and
the star wheel a certain number of notches or until no
maintenance requirements cards (MRCs). An
dragging noise is heard between the drum and the
operational check is usually conducted daily.
shoes.
O n n o n p ow e r e d e q u i p m e n t , t h i s c a n b e
NOTE: Unless thoroughly familiar with the type
accomplished by attempting to move the vehicle with
of brakes to be adjusted, you should carefully follow
the brakes set. Similarly, emergency or parking brakes
the procedures outlined in the manufacturer's service
of powered equipment can be checked by applying
manual.
power to the wheels with the brakes set.
WARNING
A road test is usually conducted for the operational
check of the wheel brakes of powered equipment. The
When working on brakes it is usually necessary to
brakes must stop a moving vehicle in a reasonable
jack up the vehicle. When doing so, be sure to
distance. After the vehicle is stopped, the brake marks
observe these precautions: (1) Place the proper
on the roadway should be inspected to see if there is an
rated jack stands under the vehicle when it is
indication of any one wheel braking more than the
raised. (2) Never work under a unit using a jack
others. If the brakes do not stop the vehicle within the
only. (3) Before using a hydraulic jack, make sure
prescribed distance, are not equalized, grab, or do not
it is filled with fluid and has no apparent leaks. (4)
hold, the necessary adjustments or repairs must be
Aboard ship, tie or chain the unit down while it is
made.
on jack stands.
The wheel brake assembly must be visually
inspected at specified intervals. To do this, you must
BRAKE INSPECTION AND
remove the wheel and brake drum. Clean the dust and
MAINTENANCE
crud out of the assembly, taking care not to breathe the
Frequent brake inspections are necessary to ensure
asbestos dust. You should use an asbestos vacuum
safe operating conditions. Brake inspections are not
cleaner or a wet spray-type cleaner and respirator.
made just to comply with regulations but to ensure
Ensure you meet all EPA, LOCAL COMMAND, and
safety of personnel and equipment. Defective brakes
NAVOSH REQUIREMENTS prior to doing brake
are a contributing factor to many accidents that might
work.
have been avoided with frequent and thorough brake
The brake assembly should be checked for loose or
inspections.
broken brake shoe retracting springs, worn clevis and
Like most components of support equipment,
cotter pins in the brake operating mechanism, and
indications of grease or oil leaks at the wheel bearing
brake assemblies require both operational and visual
2-25
